Hi deya... I do not use 1by1 player, but I might be able to provide some help.
When in the Enhancer settings tab, I was not able to check the "Prelisten mode" checkbox, because its not getting enabled here for me. But, I was able to check the "Enable" checkbox which is on the left of "Prelisten mode".
If you choose any value for "Presets" like "simple loud" or anything else, and then close... it again shows [Return previous settings] everytime.
This may seem like the settings are not getting saved... but if you observe the many slide bar levels closely under the "Audio Enhancer", and make note of some values of the slide bars... you will notice the values do not change.
So, the "Presets" settings which you chose earlier... do not get changed... it just shows [Return previous settings]. But, the settings do get saved.
I think you can also tell this by the slight change in sound effects, as a result of choosing "presets".
Well, this is what I observed. I think I may be right
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